Device for operating open-hearth-furnace dampers



May 5, 1925. l,536,226

C. E. LEHR DEVICE FOR OPERATING OPEN HEARTH FURNACE DAMPERS Filed oct. 21, 1922 2 sheets-sheet 1 C` E. LEHR DEVICE FOR OPERATING OPEN` HEARTH FURNACE DAMPERS May 5, 1925.

med oct. 21; 1922 2 Sh-ees-Sheet 2 I 3141x214* o@ Patented May` 5, 1925.

UNlTEDsTA'TEs PATENT OFFICE;

CHARLES E. LEER, OF BETHLEHEM, PENNSYLVANIA, ASSIG-NOR TO BETHLEHEM f STEEL COMPANY, A 4COBEOVRATION' OF PENNSYLVANIA.

DEVICE FOR-OPERATING OPEN-HEARTH-FURNAGE' DAMPERS.

Application led october 21, 1922. .Serial No. 596,020.

To all whom t may concern:

Be it known that I, CHARLES E. LEER, a citizen. of the United States, and residing at Bethlehem, Lehigh'A County, State of 6 Pennsylvania, have invented certain new' use in the production of steel by the openv hearth process. In the patent to Aubert 1,304,725 granted May. 27, 1919 a furnaceis illustrated and described which is provided with means for varying the eective areas of the furnace ports at the ends of the furnace so that the incoming fuel may be introduced through a relatively restricted inlet orifice and the outgoing products of combustion may be allowed to escape through an orifice of considerably larger size. The. furnace ispreversible and the port area regulating means may be operated so that either end of the furnace may be the inlet end and either end the outlet end. `In a furnaceof this character it is permissible to introduce high velocity gases, thus increasing the speed of melting of the charge and the production of the furnace, without at the same time decreasing the effective life of the furnace, since the outgoing products of combustion will pass from the furnace at moderate velocity, due to the greatly enlarged area of the furnace outlet port. The port restricting means at the ends of the furnaces are, in accordance with the Aubert invention, regulated individually by hand.

provide, in connection with a furnace having port restricting means of the general character described in the Aubert patent, means for effecting the operation of the port restricting means at the opposite ends of the furnace simultaneously upon a reversal of the furnace. The invention will be disclosed as incorporated with the furnace illustrated, described .and claimed in application Serial No. 559,381, filed May 8, 1922, by R. S. A. Dougherty which furnace is of the Aubert type, but in which the port restricting means comprises a damper at each end ofthe furnace positioned between the combustion chamber and the ports leading The object of the present invention is to.

to the regenerators, which damper may be moved into or out of the throat or conduit connecting the combustionV chamber andregenerator ports through a lslot or aperture in the furnace roof. The invention may be applied, however, to other furnaces embodying the principle of the Aubert invention to effect the simultaneous operation of the dampers, as will be seen by those skilled in the art. An important feature'of the invention consists in the provisions of means whereby the adjustment of one damper may be effected, while the furnace is in operation, without adjusting the other, thisvmeans. being conveniently and manually operable by the furnace attendant. The' effective area of the inlet conduit may be varied by this means without varying the eective area of the outlet conduit. Other novel features of the invention will be apparent from the dis'- closure thereof-in the following description and; in the accompanying drawings, in which:

Fig. 1 is a top view, partly in plan and partly broken away, of a furnace of the `type indicated having the invention incorporated therewith;

Fig. 2 is a section on line 2--2 of Figure A1; and

Fig. 3 is a perspective view'of the port 86 'area controlling means.

The furnace comprises essentlally a hearth 1() and roof 11 which enclose, together with the side walls 12, a combustionspace 13 in which the gases vare burned. Furnace ports 14 and 15 are located at the ends ofthe furnace, each of theseports being adapted to serve as an inlet port for fuel or as an outlet port for products of combustion. Conduits 16 and 17 connect the respective furnace ports with the regenerator.v ports AA and G, G respectively at the ends of the furnace. xThe air is discharged into the conduits 16 and 17 from the ports A andv A alternately and gas is discharged from 100 ports G and G alternately. i j

Slots 18 and 19 are provided in the'roof 11 and dampers 20 and ,21 are positioned to be inserted through said slots into the'conduits connecting the furnace portsv :with the 105 regenerator ports, for the purpose of varying the effective area of these conduits. The dampers are preferably downwardly and inwardly inclined as shown and are guided in trackways 22 and 23 in the side walls'of 110 the furnace. The side walls may have reentrant portions as shown in Figure 1 which constitute the well known monkey walls.

The frame of the furnace, comprising the usual beams and buck stays, F and supported on this frame is the means for effecting the operation and adjustment of the dampers. The tops of the dampers are connected by a rope 2.5 which passes over pulleys 26 and 27 respectively at the ends of. the furnace and pulleys 28, 29 and 30 at the middle. All of these pulleys are fixed with the exception of pulley 30 which may be adjusted transversely of the furnace to lengthen or shorten as desired, the effective length of the rope or cable 25. Pulley 30 is rotatably supported on the end of a shaft 31 which extends through brackets 32 and 33 respectively. Shaft 31 is provided with a keyway and a key 34 on bracket 32 extends into this keyway to preventfthe shaft from rotating. The outer end of shaft 31 is threaded and has threaded engagement with an axial recess in the hub of wheel 35, which wheel is held against movement laterally of the furnace by any suitablemeans but is freely rotatable. A sleeve 36, rigidly secured to Wheel 35, may extend through bearing 33 if desired, as shown in Figure 1, to hold the wheel 35 againstv axial movement, shaft. 31 having threaded engagement with sleeve 36 as well as wheel 35. An end- VA:as

less chain 37 extends around and has frictional or positive engagement with wheel 35, and hangs downwardly to within reach of thefurnace operaton It will be obvious that by rotating wheel 35 in one direction .l by means of the chain the effective len h of cable 35 may be increased, or by rotating it in the other direction the this cable may be decreased.

A cable 38 is secured to cable 25 at 39, this cable extending over ulley 27 and over a pulley 40 at the end o? the furnace, and having attached to its vopposite end a weight 41. Weight 41 normally tends, therefore, to lower damper 21g to its lowest position of adjustment and to raise damper 20, as shown in Figure 2.

Power means is utilized to raise damper j 21 and lower damper 20 and this means includes an electric motor 45 conveniently positioned adjacent .the furnace. This motor operates, through suitable intermediate gearin a crankV arm 46 connected b means of a ca le 47 with the damper 2 1, t is rope passing over direction changin pulleys 48 and 49 and 'over pulle s 26 and 2 The ul-` ley 26 is provided wit two grooves in w ich 'the cables 25 and 47 are separately.- containedz and the pulley 27 is provided with threeindividual grooves for the cables 25, 38 and 47 resplectively. The length of crank sitions of thendampers may r completely is indicated at effective length of that in rotatin 180. the po` reversed, andthe motor 45 is under the control of the operator or may be. connected for automatic operation with the main furnace reversing valves, which are not illustrated.

Stops are provided for limiting the upward movement of the dampers 20 and 21, these stops being indicated respectively lat 50 and 51 and being rigidly supported from the frame'of the furnace. It will be seen that by utilizing the above construction the dampers are not only to be quickly reversed in position when the furnace is reversed but the damper at the incoming end may be adjusted as desired, independently of the damper at the outgoing end. Such adjustment may be frequently desired in the operation of the furnace, because of variations in the pressures of the gas and air being supplied,jthe composition of the gas, and

the attendant to manipulate chain -37 to either raise or lower the same. If he shortens the effective length of cable 25 damper 21 will be raised. If he lengthens cable 25 it will be lowered, and movement of `^the damper 20 is prevented inV the meanwhile since this damper is tightly held against its stop 50 by the weight 41. This is a permanent adjustment and when damper 20 is lowered and damper 21 raised, upon reversal of the furnace, d amper 2() will be positioned within the furnace exactly as damper 21 had been positioned at the opposite end, the length of cable 25 being unchanged by the reversal.

To one skilled in the art the advantages of this invention will be apparent and it will also be obvious; that the design and arrangement of the damper operating means may be considerably varied Without departl ing from the scope of the invention.

' Having thus described the invention what cluding in combination, a reversible fur-v nace having a combustion chamber and a conduit atl each end` for the passage of incoming fuel or outgoing products of com.- bustion, a'device associated with each conduit for decreasing its gas carrying capacity when used as an inlet conduit for fuel` and increasing its as carrying capacity when used as an out et conduit for products of combustion, and means connecting said de-Vl vices for simultaneous operation, said means permitting adjustment of one of said devices'without adjustment of the other.

2. Mechanism of the class described including yin combination, a reversible furnace having a combustion chamber and a conduit at each end for the passage of incoming fuel or outgoing products of comincreasing its l v `iasaaaae ustirfm, a device associated withv each 'conuit or) decreasing its gas carrying capacity when'used as an'inlet conduit for fuel and carrying capacity when \used' as an ouzts `conduit forrproducts of' combustion, means connecting said devices' for simultaneous operation, a power element for o rating said means, and said meansv inclu ing a manually operable member for adjusting Ioneof'said devices'without adthe other.

y justinhg n 3. echanism ofthe class described injcluding, in combination, a reversible furnace having a combustinn chamber and a conduitat each end for the passage of ine` coming fuel oroutgoing'products of combustion, a device associated with each con- -duit for decreasing its gas carrying capacity when -used as an inlet conduit for fuel and increasing its --ca ing capaci? when l used as an out et con uit for pr ucts of i fat its ends for fuel and combustion, means connecting said devices for'simultaneous o ration, a power element for operating saidpe means inone' direction, and a weight for operating said means n the opposite direction. Y

.l A4. An open hearth furnace having -ports roducts of` comf bustion, a damper movabe-transversely of,

Y each of said aurea,

each of said 'ports for" varying its ee'ctive area, and means connecting said .dampers together for simultaneous movement upon reversal ofthe furnace, sadmeans being designed and constructed to rmit one .of said dampers to adjusted while the other is stationary. j

5. An open hearth furnace having ports y at `its ends for fuel and roducts of combustion, a damperA movab e transversely' of ports for'varying its effective a cab e connecting `said dampers whereby .they may be simultaneously opvaryin n ingl sald dampers whereby they maybe 'K erated;Y when the, furnace is reversed, and

simultaneously operatedwhen .the furnace is.reversed, and means .for adjusting the effective length of the cable;

7. An open hearth furnace having ports atits ends for fuel and roducts of com-- b ustion, a damper movab e transversely of each of said rts for fvaryingdts effective' arca, a cabin?) connecting said dampers whereby 'A they may be simultaneously operated when the furnace is reversed,and

means for adjusting theefective length of I the cable, said means including a pulley engaging the cable and mechanism for moving the pulley in a direction transverse to the general direction of the ro 8. An open hearth furnace aving ports at its ends for fuel and roducts of combustion, a damper mo'vab e transversely of each of said rts for varying its'eil'ective area, a. cab e lconnecting said dampers whereby Vthey may be simultaneously operated when the furnace is reverse and means for adjusting the effective length of Y lthe cable, said means including -a pulley engaging the cable and screw means for.

moving the pulley in a direction transverse to the general' direction of the cable.

9. An open hearth furnace having ports at its ends for fuel and roducts of combustion, a vertically mova le damper movable transverselyfof Veach of said ports for varying the effective area, a limiting the upward movement ofeach damper, a

cable connecting said dampers whereby they maybe simultaneously operated when the furnace is reversed, and means for adjusting the elective len h of the cable.

10. An open heart furnace having ports at its ends for fuel and products of combustion, a Ydamper substantially vertically movable transversely of each of said ports for varying its effective area, a cable con- I nectingsaid 'dampers whereby they may be simultaneously operated .when the furnace is reversed, means normally tending to lower one of said dampers and to raise the other, and. power 'means for moving the dampers in the olpposite direction.

In testimony w ereof I hereunto aix my signature.`

' CHARLES E. LEHR. 

